2 answers

Of course, Tengu is good for running L3 or even L2 missions with his heavy but little-sized missiles. At L5 he is not that good though due to lack of less-than-BS targets to shoot at. And his tank is not enough for L5s. And about drones - Tengu misses the drone bay completely, there is no setups which will allow you to use drones.

Tengu is an excellent mission runner and I regularly use it for lvl4's especially when there is a large amount of Frigs, Cruisers and BC's. You can have drones with the Tengu - check out sub system Tengu Offensive - Rifling Launcher Pattern - this gives you :-
Bonus:
10% bonus to ECM target jammer strength per level
5% bonus to Heavy, Heavy Assault and Assault Missile Launcher Rate of Fire per level and
Drones 50m3 25 Mbit/sec

I do not use this as I feel that heavy missiles with a target painter clear frigs fast enough without drone assistance but it is there if you want to use drones with the Tengu.